Pump motors



Feb. 14, 1937 w. s. ILOYWELL 3,303,750

PUMP MOTORS Filed April 1, 1965 2 Sheets-Sheet 1 I NVENTOR.

/ WILLIAM S. POWELL BY M MAHgIVEY, MILLER 8 RAMBO ATTORNEYS Feb. 14,1967" w. s. POWELL 3,303,750

PUMP MOTORS Filed April 1, 1965 2 Sheets-Sheet 2 INVENTOR.

E; E. J WILLIAM s. POWELL MAHBO NEY ILLER 8| RAMBO ATTORNEYS UnitedStates Patent 3,303,750 PUB KP MOTORS William S. Powell, R.F.D. 2,Granville, Ohio 43023 Filed Apr. 1, 1965, Ser. No. 444,698 12 Claims.(Cl. 91273) My invention relates to a well pumping unit and particularlyto an apparatus useful in pumping liquid from a well in which naturalgas is present or accumulates at intervals, for example, from an oilwell. The pump of my invention will pump the oil up from the well into astorage tank or pipe line or any other selected remote location.According to my invention, preferably the pressure of the natural gas inthe well is used as the pumpactuating means rather than a fuel-burningmotor or an electric motor thereby resulting in an economical andautomatic pumping apparatus.

With :many oil wells, especially those that are lowproducing, it isimportant that pumping apparatus be employed which will operate veryeconomically and preferably only at necessary intervals to handle theaccumulation of oil in the well. This accumulation usually occurs withan increase in natural gas pressure in the well. In the past, it hasbeen the practice with low-producing wells to have pumps which areactuated by internal combustion engines. Therefore, it is usuallynecessary to have a man travel through an area, manually start each pumpmotor and wait for a period while the pump lifts from the well theaccumulation of oil, and then stop the motor. If electrically-actuatedpumps are used, it is necessary to run electric lines to the pump site,which, even if available, are costly, and also to manually start andstop the motor; The electric motors or the internal combustion motorscan be equipped with automatic starting and stopping syste ms buttheseare costly and not fool-proof and add to the maintenance cost ofthe electric or internal combustion motors. Also, they still require theconsumption of relatively expensive fuel or electric current. Hydraulicpumping'units have also been provided in the past but these are also tooexpensive to install, operate and maintain, especially for low-producingwells. All of the above-discussed factors are particularly pertinent inconnection with the low-producing wells to make the recovery of oiltherefrom economical.

It is, therefore, the main object of my invention to provide afluid-actuated well-pumping unit which is of simple,

economical, rugged and long-lasting construction and which preferablyemploys natural gas accumulations in the well as the pump-actuatingfluid medium and, consequently, which makes unnecessary the expenditureof combustible fuel or electric current to actuate the pump.

Another object of this invention is to provide a wellpumping unit of thetype indicated which is provided with a control arrangement so that itwill be started and stopped automatically under control of theaccumulation of natural gas in the well and, therefore, will onlyoperate when the well needs pumping but will automatically functionduring those periods.

Still another object of this invention is to provide a well-pumping unitwhich is not only fluid-actuated, preferably using the natural gas inthe well as the actuating medium, but is also preferably equipped with avacuum ballast counterbalance arrangement for the pump rod string of thewell which is created upon initial operation of the fluid-actuated pump.

Various other objects will be apparent.

As indicated, my pumping unit is designed to utilize fluid pressure andpreferably the natural gas pressure in the well as the pump-actuatingmedium. This gas pressure is usually present between the oil pump lineand the casing. It is utilized, according to my invention, by lead-Patented Feb. 14, 1967 ing it through proper piping and control valves,including a quick-acting reversing valve, into the expansion chamberwithin a bellows which is operatively connected to the pump rod stringof the well. Expansion of this bellows by the admitted natural gas willlift this pump rod string and operate the pump in the well and, underthe control of the reversin valve, exhaust of gas from the bellows willbe started near the end of the upstroke so that the weight of the rodstring will cause the bellows to collapse to its original down orstarting position. In addition, a vacuum chamber is provided around thebellows and means is provided for pumping out that chamber during theinitial operation of the pumping unit, and later if needed, so as tocreate a vacuum ballast force in that chamber which will act on thebellows as a counterbalance force for the pump rod string.

In the accompanying drawings, I have illustrated a preferred embodimentof my invention and in these drawings:

FIGURE 1 is a vertical schematic sectional view of the fluid-actuatedpumping unit of this invention showing it in its up position.

FIGURE 2. is a similar view but showing the unit in its down position.

With particular reference to the drawings, the pumping unit of myinvention includes an outer housing or case 1 which is preferably ofsteel and is of annular horizontal cross section with an upper convex ordome-shaped top 1a and a lower concave bottom or base 11 which isconnected thereto at a sealed but separable annular joint 10. The case 1is made sufficiently strong to resist outside atmospheric pressure evenwhen the space within it is evacuated to a low degree. The pumping unitis mounted directly on the well on the casing 16a and the base 11 is ofsuch strength that it can support the entire pump assembly including thepump shaft or sucker rod 16, the pump cylinder (not shown) and thecolumn of oil in the oil pipe 16b, the assembly being supported from thebase 11 by a suitable collar and seal arrangement 18. Leading from theoil pipe 16b is an oil discharge line 162 which will conduct the oilpumped from the well to a pipe line or storage tank. A suitable oil wellpump rod seal is indicated at 14 for providing a fluid seal around therod 16 directly below the seal 18. Gas from the casing 16a will enterinto a branch line which is connected thereto and which is controlledmanually by a valve 23 which may be a standard gas key or any othervalve that can be manually set for a selected flow.

Within the outer case 1 is another case 2 of inverted cup-like form andof the same general outline as the outer case 1 to provide therewithinan inner chamber 22 in which the bellows 9 is disposed. The case 2 isspaced from the corresponding sides and top of the outer case 1 toprovide an outer chamber 21 which may be termed a plenum chamber andwhich is closed to the atmosphere. The lower edge of this case 2 engagesthe upper surface of the bottom or base 11 along an annular separablesealing and connecting joint 10a.

The upper dome-shaped top 2b of the case 2 is provided with an exhaustoutlet controlled by a ball-check valve 6 which is preferablygravity-seated. This ball and associated seat is located at the lowerend of a vertical tube 7 which has its lower end sealed to the top 2band its upper end passing upwardly through a sealed opening in the top1a of the case 1. Thus, the bellows-enclosing inner chamber 22 cancommunicate with the atmosphere through this tube 7 under the control ofthe ball-check valve 6. An additional valve port is provided in the top2b and is under the control of a spring-biased valve 20 in which thespring will act upwardly in the closing direction. Positive pressure inthe inner chamber 22 will serve to seat it upwardly whereas negativepressure therein,

when sufficiently low, will tend to unseat it. A valve port 17a isprovided in the side wall of the case 2 and is shown under the controlof a manually adjustable needle valve '17 which is adjustable from theexterior of the case 1. These valves 17 and 20 will controlcommunication between the chambers 22 and 21 and are the only passagestherebetween.

The bellows case 2 has the annular bellows 9 disposed therein forvertical expansion and contraction relative thereto and this bellows hasthe gas-receiving chamber 19 formed therewithin. This bellows may beformed of a suitable strong flexible material, such as. nylon reinforcedneoprene, or other material which can be molded into proper shape andwill adequately withstand gas pressure,

oil fumes and the necessary repeated flexing and folding without losingits shape or otherwise quickly deteriorating. The lower end of thisbellows may be sealed to a ring 100 which is attached to the base 11 atthe separable joint 10a and its upper edge may be attached to the steelcap or head 3 of the bellows at a separable sealed joint 10d. This capor head 3 is preferably dome-shaped to conform to the shape of the cap2b of the case 2 and is suificiently strong to lift the pump shaft 16and the column of oil. It is connected at a connecting and sealing unitof a suitable type, to the upper end of the pump shaft 16 so as toprovide the lifting capacity to carry the weight of the pump shaft andassociated pumping parts and the oil being lifted in the pumpingoperation.

The cap 3 is also provided with a depending valveactuating stud 4 whichis screwed upwardly into a threaded socket in the cap for relativevertical adjustment. This stud 4 is one of themeans for actuating thequickacting control or reversing valve indicated generally at 12.Another means for actuating this valve is provided by a flexibleactuating pull-producing connection between the valve 12 and the cap 3and is shown as comprising a line 15 which may be of suitable flexiblematerial such as stainless steel wire, cable or rope, and which isconnected to the lower side of the cap 3 at a connection 15a and to oneend of a lever 12a of the valve at 1512.

The valve 12 may be termed a positive flip-flop or snap-action valve andwill be instantaneous in its action as the bellows head 3 approaches theupper and lower limits of its stroke. It is' provided with intake andexhaust ports connected to the bellows chamber 19. It can be any of thequick-acting types commonly available and must be capable of instantlyopening the exhaust valve port as the intake valve port is closed at thetop of the bellows stroke and, in like manner, of instantly closing theexhaust valve port and opening the intake valve port at the bottom ofthe stroke. The valve 12 is mounted on the bottom 11 and the ring 100and for illustrative purposes is shown as including a housing 12b whichis divided into four chambers comprising the lower chambers 12c and 12dand the upper chambers 122 and 12 The lower inlet chamber 120 connectswith and receives gas from the pipe 160. The lower outlet chamber 12dconnects to a low-pressure gas line 16d which will conduct the gas to apoint of use or vent it to the atmosphere and which may be provided witha suitable check-valve. The upper chambers 12e and 12 communicatedirectly with the chamber 19 within the bellows 9. Between the chambers12c and 122 is a valve seat 12g and between the chambers 12d and 12 is avalve seat 12h.

The details of the valve-actuating mechanism may vary but the mechanismis shown as comprising upwardly seating valve members 12i and 12 forcooperating with the respective seats 12g and 12h on the lower end ofstems which pass upwardly into the chamber 19 and are pivotallyconnected to the valve lever 12a at the respective points 12k and 12ladjacent its opposite ends. The lever 12a is pivoted for, verticalswinging movement at point 12m intermediate its length to a fixedsupport 1211 upstanding in the chamber 19. An off-center snap-actingspring arrangement of the usual type is indicated for quickly snappingthe valve lever 12a in each of its two respective final positions afterit is actuated or triggered by either line 15 or stud 4. Thisarrangement is shown as comprising a compression spring connectedbetween the upper projecting end of the support 1211 and the upper endof an upstanding arm which is disposed on the valve lever 12a inalignment with the pivot 12m thereof. The valve member 121 cooperateswith the seat 12g to provide an intake valve and the valve member 12jcooperates with the seat 12h to provide an exhaust valve for the bellowsexpansion chamber 19 and these valves are alternately opened and closed.

The gas line which conducts gas from the well to the valve 12 preferablyis provided with a flow control valve unit 13, which is of a suitabletype, including a timing device which will automatically open and closeat timed intervals to supply the actuating gas pressure for the pump.For wells that require intermittent pumping, the timing mechanism of thevalve 13 may be of the pressure-operated type so as not to require themanual winding of a spring-type valve.

If insuflic-ient gas pressure is present in the well to operate thepump, a source of air pressure, such as a motor or engine (not shown),may be used for supplying the necessary actuating pressure. Also, if thepump is not to be equipped with the vacuum ballast counterbalancearrangement, and the usual mechanical counterbalance is connected to thepump (not shown) the case 1 will be eliminated and the case 2 will opencontinuously to the atmosphere. In this latter example, the case 2 wouldserve only as a protective cover for the bellows 9.

The pumping unit, as shown, will operate normally in the manner now tobe described, assuming that the air has been substantially removed fromthe inner chamber 22 and the outer chamber 21 in a manner to bedescribed later. Also, assuming the manual valve 23 in the gas line 166is open, the valve 13 will open automatically at preselected intervalsto supply gas pressure at the valve 12. Also assuming the bellows 9 isin its lowermost or collapsed condition, as shown in FIGURE 2, and thevalve 12 is in the condition illustrated with the inlet valve member 12iunseated and the exhaust valve member 12f seated, the gas under pressurewill flow past the valve seat 12g into the bellows expansion chamber 19within the bellows 9 thereby causing the bellows to expand upwardly andlift the pump rod 16. The valve member 12 at this time will be seated tocut-off connection of the bellows expansion chamber 19 with the gas line16d. The bellows cap 3 will be moved upwardly in the case 2. As thebellows 9 nears the extent of its expansion and the cap 3 approaches theextent of its upward movement to a level adjacent the cap 1a, theflexible line 15 is completely extended and will exert a pull on thevalve lever 12a and trigger the valve mechanism so that, as shown inFIGURE 1, it will snap the valve into its other position where the inletvalve member 12i is seated and the exhaust valve member 12j is unseated.This will instantly interrupt flow of gas from the gas line 160 into theexpansion chamber 19 within the bellows 9 but will connect that chamberto the gas receiving line 16a. The gas within the chamber 19 will nowquickly escape past the valve seat 12h to the gas line 16d and this willinstantly stop expansion of the bellows 9 and upward movement !of itscap 3 and immediately permit the weight of the rod 16 and suspended pumpparts to exert a gravity pull on the bellows cap 3 and cause the bellows9 to collapse. As the bellows cap 3 approaches its lowermost position,the stud 4 will strike the valve lever 12a and trigger thevalve-actuating mechanism to cause it to snap the valve again into theposition shown in FIGURE 2 at which time the gas supply line 160 willagain be connected to the bellows expansion chamber 19 and the gasreceiving line 16d will be disconnected therefrom at the reversingcontrol valve 12.

The above-indicated cycle normally will be repeated over and over sothat as the bellows cap 3 reaches a pre- .5 determined height, theactuator 15 for the valve 12 causes it to close the input valve portthereof and at the same instant open the exhaust valve port thereofallowing the bellows 9 to collapse as the weight of the pump shaft 16and associated parts draws it down to the starting position and as itnears that position, the actuator 4 for the valve causes it to close theexhaust valve port and open the intake valve port thereby startinganother cycle and continuing these cycles until the timer valve 13 orthe manual valve 23 is closed to interrupt the flow of gas to the valve12.

As previously indicated, it is preferred to have a vacuum ballast orcounterbalance arrangement for counterbalance of the pump rod stringwhich usually has its deadweight counterbalanced mechanically. For thispurpose, the outer plenum chamber 21 is provided, in conjunction withthe inner chamber 22, by enclosing the case- 2 within the case 1 andproviding the cooperating valve arrangements described above includingthe valves 6, 17 and 20. 'In the initial operation of the pump, thevalve 17 is closed manually. As the bellows cap 3 rises, it forces airor gas in the inner chamber 22 out past the valve 6 to the atmosphere.Also, the valve 20 is closed by positive pressure in the chamber 22.Both the bellows expansion chamber 19 and the plenum chamber'21 will notcommunicate with the atmosphere on the up stroke of the bellows but theinner chamber 22 will exhaust thereto through the valve 6. As thebellows 9 collapses and the cap 3 thereof moves downwardly, a negativepressure is created in the inner bellows enclosing chamber 22 above thecap 3. The resulting pressure differential, caused by this pumping-outoperation, between the positive gas pressure beneath the cap 3 and thenegative pressure above the cap 3, when the cap reache its lowermostposition, will serve as a counterbalance force which will aid incounter'balancing the pump rod 16 and weight suspended therefrom, and instarting the up or expansion stroke of the bellows.

The control valve 17, between the outer plenum chamber 21 and the innerbellows-enclosing chamber 22, regulates an exchange of the negativepressure air between them after the initial starting of the pump and theresulting build-up of the vacuum or negative pressure. When the pump isfirst started, the valve 17 may be closed manually, a indicated above,to prevent air or gas from entering the outer chamber 21 through thevalve port 17a. The bellows 9 will pump out air from the inner chamber22 on the upstroke, through the valve 6, and will draw air from theouter chamber 21 on the downstroke, through the spring-loaded valve 20.Before the negative pressure in the inner chamber 22 is of a degreesuflicient to stop the downward motion of the bellows head 3, the valve17 is gradually opened manually until a regular reciprocating cycle ofthe pump occurs and this can be controlled in frequency by a balancingof the manual gas or air valve 23 and the manual control valve 17. Thenegative pressure above the cap 3 is created during pump-out of air asthe bellows collapses to provide a void space in the inner chamber 22without drawing air from the atmosphere, since during the downstroke,the chamber 22 only communicates with the outer plenum chamber 21,through the valve 20 which opens at -a selected negative pressuretherein. The valve 20 will close, when for any reason, during theoperation of the pump, the pump loses its prime or air finds its wayinto the inner chamber 22 creating a positive pressure therein.Thereafter the bellows assembly can pump out the air through the escapeball check valve 6 to the atmosphere until the partial vacuum is builtup in both the inner chamber 22 and the outer chamber 21 to provide thecounterbalance effect.

The use of the bellows arrangement in an oil-well pumping apparatus isparticularly important due to the nature of that operation. It isimportant to have equipment which will resist surface erosion bychemicals present in the gas in the well heads and the bellows may bemade from material which meets this requirement. Also, the

material of the equipment must resist abrasion by the abrasive sand andother materials brought up on the well head sucker rod and the materialof the bellows meets this requirement. Also, the large area volumerequired for effectively utilizing the energy in the expandable gas andthe oil head pressure must be great and this can be accomplished withthe bellows without undue bulk and weight, which would be necessary witha piston and cylinder arrangement. Also, the piston to cylinder slidingcontact areas for a large pumping unit of this type would be very greatand there would be danger of fluid by-pass at these areas from one sideof the piston to the other, whereas this would not be present in abellows unit since the bellows provides a completely enclosed unitexcept at the connected pump rod.

Various other advantages will be apparent.

Having thus described my invention what I claim is:

1. A well-pumping unit for use on a well head having a pump rodextending therefrom comprising a support adapted to be disposed at thewell head, an expansible bellows mounted on said support and having afluid-receiving expansion chamber therewithin, said bellows includingmeans for connecting it to said rod, a fluid inlet for conductingactuating fluid into said chamber for expanding said bellows and a fluidoutlet for exhausting fluid from said chamber to permit collapsethereof, a reversing valve means for alternately closing said inlet andopening said outlet and opening said inlet and closing said outlet, andcontrol means operatively connected to said bellows for actuationthereby to control said valve in accordance with the expansion andcollapse of said bellows.

2. A well-pumping unit for use on a well head having a pump rodextending upwardly therefrom comprising a base support adapted to bedisposed at the well head with the rod extending slidably upwardlytherethrough, an expansible bellows mounted on said base support, a capon the bellows having means for connecting it to said rod, a fluid inletfor conducting actuating fluid into said chamber for expanding saidbellows and a fluid outlet for exhausting fluid from said chamber topermit collapse thereof, a reversing valve means for alternately closingsaid inlet and opening said outlet and opening said inlet and closingsaid outlet, and control means connected to said bellows cap to controlsaid valve in accordance with the vertical movement thereof produced byexpansion and collapse of said bellows.

3. A well-pumping unit according to claim 2 in which said valve meanscomprises actuating means having a snap-action for moving it into eitherof two positions when triggered by said valve control means, saidcontrol means comprising a flexible line connected between saidactuating means and said cap for triggering it as the bellows cap nearsits uppermost position caused by expansion of the bellows to close saidinlet and open said outlet and contacting means carried by said cap andengaging said valve actuating means for triggering it as the cap nearsits lowermost position caused by collapse of the bellows to open saidinlet and close said outlet.

4. A well-pumping unit according to claim 2 including an inner caseenclosing said bellows and cap to provide an inner fluid chamber, anouter case enclosing said inner case to provide an outer fluid chamber,a passageway leading from said inner chamber to the atmosphere andhaving a one-way vent valve therein for permitting exhaust from saidinner chamber as the bellows expands to move the cap upwardly thereinbut preventing intake of atmospheric air as the bellows collapses tomove the cap downwardly in said inner chamber, and valve meanscontrolling communication between said inner chamber and said outerchamber for pumping air from said chambers and expelling it to theatmosphere through said vent valve by operation of said bellows.

5. A well-pumping unit according to claim 4 in which said last-namedvalve means includes spring-'pressed'means and manually adjustablemeans.

6. A well-pumping unit according to claim in which said spring-pressedvalve means opens under a selected negative pressure in said innerchamber and closes under positive pressure in said chamber.

7. In combination with a well having pumping means including a pump rodextending from the head thereof, a gas supply line leading from the welland a gas receiving line; a support mounted-at the well head, anexpansible bellows mounted on said support and having an expan-.

sion chamber therewithin, means connecting said bellows tosaid pump rodso that expansion and collapse of the bellows will reciprocate said rod,a gas inlet leading from said gas supply line into said chamber and agas outlet leading from said chamber to said gas receiving line, areversing valve means for alternately closing said inlet and openingsaid outlet and opening said inlet and closing said outlet, and controlmeans operatively connected to said bellows for actuation thereby tocontrol said valve in accordance with the expansion and collapse of saidbellows.

8. The combination of claim 7 including a timing valve connected to saidgas supply line for controlling the supply of gas at timed intervals tosaid inlet.

9. The combination of claim 7 in which said means for connecting thebellows to said pump rod comprises a cap on the bellows verticallymovable upon expansion and collapse of the bellows, said valve controlmeans being connected to said cap to control said valve in accordancewith the vertical movement thereof produced by expansion and collapse ofsaid bellows.

10. The combination of claim 9 including an inner case enclosing saidbellows and cap to provide an inner fluid chamber, an outer caseenclosing said inner case to provide an outer fluid chamber, apassageway leading from said inner chamber to the atmosphere and havinga oneway vent valve therein for permitting exhaust from said innerchamber as the bellows expands to move the cap upwardly thereinbutpreventing intake of atmospheric air as the bellows collapses to movethe cap downwardly in said inner chamber, and valve means controllingcommunication between said inner chamber and said outer chamber forpumping air from said chambers and expelling it to the atmospherethrough said vent valve by operation of said. bellows.

11. The combination of claim 10 in which said lastnamed valve meansincludes spring-pressed means and manually adjustable means.

12. The combination of claim 11 in which said springpressed valve meansopens under a selected negative pressure in said inner chamber andcloses under positive pressure. in said chamber.

References Cited by the Examiner v UNITED STATES PATENTS 862,867 8/ 1907Eggleston. 7 2,110,393 3/1938 Edwards 52 2,408,075 9/1946 Kowalski etal. 3,012,513 12/1961 Knox 103-52.

ROBERT M. WALKER, Primary Examiner.

1. A WELL-PUMPING UNIT FOR USE ON A WELL HEAD HAVING A PUMP RODEXTENDING THEREFROM COMPRISING A SUPPORT ADAPTED TO BE DISPOSED AT THEWELL HEAD, AN EXPANSIBLE BELLOWS MOUNTED ON SAID SUPPORT AND HAVING AFLUID-RECEIVING EXPANSION CHAMBER THEREWITHIN, SAID BELLOWS INCLUDINGMEANS FOR CONNECTING IT TO SAID ROD, A FLUID INLET FOR CONDUCTINGACTUATING FLUID INTO SAID CHAMBER FOR EXPANDING SAID BELLOWS AND A FLUIDOUTLET FOR EXHAUSTING FLUID FROM SAID CHAMBER TO PERMIT COLLAPSETHEREOF, A REVERSING VALVE MEANS FOR ALTERNATELY CLOSING SAID INLET ANDOPENING SAID OUTLET AND OPENING SAID INLET AND CLOSING SAID OUTLET, ANDCONTROL MEANS OPERATIVELY CONNECTED TO SAID BELLOWS FOR ACTUATIONTHEREBY TO CONTROL SAID VALVE IN ACCORDANCE WITH THE EXPANSION ANDCOLLAPSE OF SAID BELLOWS.